Crankshaft lathe



Feb.-20,v 1940. w. F. GROENE r AL 2,

CRANKSHAFT. LATHE I I Filed Feb. 21, 1938 4 Sheets-Sheet 1 V INVENTORS.

WILL/AM F. GROE/VE' HAROLD J. SIEKMA/VN Jamar/M. 1 BY \QMMA WITNESS.

ATTORNEY.

Feb. 20, 1940. w, GRQENE AL 2,191,347

CRANKSHAFT LATHE I Filed Feb. 21, 1938 4 Sheets-Sheet 2 INVENTORS.

WILL/AM E GROENE HAROLD J. S/EKMANN JMxM g QLQQM g M W/ T/VESS.

ATTORNEY.

W. F. GROENE ET AL CRANKSHAFT LATHE Feb. 20, 1940; v 2,191,347 v Filed Feb. 21, 1958 4- Sheets-Sheet s INVENTORS. WILLIAM F. GROE/VE HA ROLD J. S/EKMANN \QLQQM m'risss.

ATTORNEY.

a ents were ground in a rough grinding operation the drawings, in which:

so I It; iatherefore, the object of the present in unit. i2.

Patented FeB.2o,194o. a 2,191,347-

UNITED STATES PATENT oF -Tcs 2.191.341 camsnar'rmrns William F. Groene and Harold J. Siekmann,

Cincinnati, Ohio, assignors to The R. K. Le Blond Machine Tool Company, Cincinnati, Ohio, a. corporation of Delaware Application February 21, 1938, Serial N... 191,718

13 Claims. (Cl. 82-9) This. invention pertains to crankshaft lathe which is adapted to simultaneously finish shave and more particularly to lathes adapted to finish the line bearing diameters, to trim the fillet walls machining operations on the bearing portions of associated with said diameters and also to finish crankshafts. As an exemplary disclosure we-- machine all of the stub end and flange end por- 6 show a machine adapted to simultaneously finish tions simultaneously in a single. operation. 6 turn the line bearings, including the flange and Another object of the invention is to provide stub ends, of a multiple throw internal combusa simplified feeding arrangement whereby a sintion engine'crankshaft. The lathe of this disgle toolbar moving in a single direction is closure is one which is adapted to finish shave capable of simultaneously accurately finishing the 10- the line bearing and associated diameters and bearing diameter and also trimming the fillet 10' to finish trim the fillets adjacent said line bearwalls to a high degree of accuracy.

lugs and flange and stub end portions of crank- I Still another object of our invention is to shafts which have been previously machined in provide a novel tool holder containing a shaving such lathes as are illustrated in Patents Re. tool for accurately machiningthe diameter of a 19,905, dated March 31, 1936, Re. 20,090, dated crankshaft bearing a second series of cutting tools 15 September 1, 1936, and 2,069,107, dated January adapted to face and. neck the fillets associated 28, 1987. a with said bearings.

Heretofore, work which had been completed Other objects of this invention will be underon lathe. such as cited in the above three patstood from the following detailed description of insofar as the line bearing diameters were con- Figure I is a front elevation of a crankshaft cemed. In this rough grinding operation conlathe incorporating the features of our invensiderable time was required inasmuch as-it is tion shown adapted to simultaneously finish turn necessary in a grinding operation of this charall of the line bearings, including the flange and g5 acter to grind each of the line bearings sepastub end portions, of a crankshaft. rately in order to gain the proper degree of fin- Figure II isa right hand end elevation of the lab required. It is also found in rough grinding lathe shown in Figure I. operations that it is extremely difficult to obtain Figure 111 isa vertical transverse section theproper spacing between the fillets because through the lathe shown substantially on the 3 -of the break down of the grinding wheel side line III-IIIof Figure I. v faces, with the result of the rapid deterioration Figure IV is an enlarged portion of the Figure of the wheel under frequent dressing necessary III to more clearly show the relation of the cutto maintain the sharp corners required for these ting tools to the work piece. I I fillets. Also during the rough grinding opera- 'Fisure V is a horizontal section through the tion it is impractical to finish such portions as lathe on the line V-V of Figure IV. 35 the stub end diameters and thefiange and oil The machine comprises a base I upon which groove portions of the crankshaft. These porare mounted tailstocks 2 and 3 having the usual tions were, therefore, not finished during the centers 4 and i which may be axially reciprocated rough grinding operation and required further bythehand Wheels of the tailstocks. Also on 40 turning operations to complete them to their the base I between the tailstocks 2 and 3 are the 40 necessary high degree of turned finish. center drive chuck units 1 and 8 which carry the It was also found that before the rough grindcenter drive ring gear chuck indicated generally ing operations'couldbe undertaken it was necesat 9. Between the tailstock 2 and the center sary to re-straighten the crankshaft so that the drive chuck housing '|.is mounted on the base i excessive run-out would not damagefthe grinding the fiange end tool unit i0. Between the center 45 wheel or require excessive amount of stock to be driving chuck housings 1 and 8 is mounted on v removed by grinding which, of course, is a much the base I the center line bearing tool unit ll, slower process than that of turning in removand between the center drive chuck unit I and in: the same amount of metal. the tailstock 9 is mounted the stub end tool vention to eliminate the .above objectionable fea- Appropriate loading devices for inserting and tures in order'to-finish machine the'line bearings removing the crankshaft fromthe center drive e including the flange and stub ends of a crankchucks 9 comprise the cranes I 3 and I4 carried shaft. V on. the red I! which in turn is supported on g 1 One object of our inventionis toprovide a lathe standards it carried by the tailstocks 2 and 3- in I connected to the rock a manner fully disclosed in Patent 2,069,107, dated January 26, 1937.

The center drive ring gear chucks 9 are driven by the electric motor mounted on the motor plate It which in turn is fixed on the base of the lathe. l9, (best seen in Figure II) which engages and drives the gear fixed on the drive shaft 2| which is suitably journaled in the tool carrier units I0 and I2 and the center drive units 1 and 8. On the shaft 2|, where it passes through the units 1 and 8, are fixed driving pinions 22 which in turn drive idler gears 23 carried on studs 24 fixed in the center drive chuck units I and 8, the idler gears 23 in turn driving the respective ring gears 25 of the center drive ring gear chuck 8 so that upon rotation of the driving motor I] the center drive ring gear chuck 9 will be driven in synchronism to rotate the crankshaft C mounted therein.

The crankshaft C is gripped in the chucking devices 8 by means of a chucking mechanism for example of a character shown in Patent 2,030,020, dated February 4, 1936, and the ends of the crankshaft are supported on the centers 4 and 5 in the usual manner of a lathe.

In each of the tool carrier units III, II, and i2 is mounted a single tool bar 28 (best seen in Figure III) which is adapted to be moved to and i from the axis of the work piece 0 in horizontal plane. The tool bar is reciprocated in this manner by means of a rock shaft 21 which is rotatably mounted in suitable bearings 28 carried in the rear of the tool carrier units III, II and I2 and the center drivechuck units I and 8. On this rock shaft are fixed downwardly extending crank arms 28 which are connected to each of the tool bars 20 in the units IO, M, and I2 by means of connecting rods lll which are adiustably mounted at 2| in the wrist pins 22 of the downwardly proiecting arms 29 for the purpose of adjusting the bar relative to the work piece for final sizing of the work diameter. The rock shaft 21 is actuated by means of the fluid pressure cylinder 22 which is pivotally mounted on a pin 24 carried in the upstanding boss 25 formed integral with the tool carrier unit II and having a piston rod 30 pivotally connected at 31 to a lever arm 38 shaft 21. so that reciprocation of the cylinder 23 and its piston rod 30 will cause rocking movement of the shaft 21 and thereby simultaneously feed all of the tool bars 20 in the tool carrier units IO, N and I2 to and from the work piece 0 in the lathe. Appropriate fiuid pressure control means of conventional design for operating said cylinder Il may be employed.

Noting in particular Figures IV and V it will be noted that on each of the tool bars 20 is mounted a novel tool holder 20 which contains shaving tools 40 for accurately finishing the diameters of the bearing portions 40a of the crankshaft and also contains facing tools 4| adapted to face the side walls 42 and to neck the fillets 43 to accurate finished dimensions. Appropriate back up screws 44 and 45 are provided for respectively adjusting and holding the tools 40 and 4| in correct cutting position.

The shaving tool 40 has its cutting edge 40 lying in a plane which is parallel with the plane of feeding of the tool bars 20 and tangent to the surface of the diameter which has its cutting edge inclined at an angle to a plane passing through the axis of the work and normal to said first mentioned plane. The ob- The motor H has a driving pinion 40a being machined butarrangement being that the entire 48 is at no time operating on the di- .Iect of this cutting edge ameter 40a being machined. With the full width of cutting edge 46 of the tool thus eliminated substantially all chatter and excessive strains on the work piece are eliminated which prevents marring the accurate finish required in this type machining operation. It will also be-noted that the tools 4| for machining the fillets are so arl0 ranged in relation to the shaving tools 40, that both the tools 40 and 4| operate simultaneously upon the work piece and complete their mamining operation simultaneously. These tools 4| have their cutting edges 41 so arranged that at the completion of the cutting cycle those edges 41 blend perfectly with the machined surface 40a produced by the cutting edge 46 of the shavinz tool 40 resultingin a high degree of accuracy and finish for all of thevital surfaces 400, 42 and d8 of the crankshaft bearings. It is also to be noted, referring to Figure I, that this same arrangement is employed for machining the fiange end and the stub end portions in addition to all of the line bearing portions of the crankshaft C.

Having fully set forth and .described our invention what we claim as new and desire to secure by U. S. Letters Patent is:

1. In a lathe, a rotatable work holder adapted to engage a work piece having cylindrical and radially extending surfaces, a tool carrier movable relative to said work piece perpendicular to its axis of rotation in the work holder, a tool holder carried on said tool carrier, a shaving tool mounted on said tool holder adapted to machine the cylindrical portion of said work piece, a facing too], mounted on said tool holder adapted to machine radially extending surface on said work piece, means for rotating said work holder, and means for feeding said tool carrier.

2. In a lathe, a rotatable work holder adapted to engage a work piece having cylindrical and radially extending surfaces, a tool slide movable perpendicular to the axis of rotation of said work piece, a cutting tool mounted on said tool slide having its cutting edge in a plane which is parallel to the movement of said tool slide and tan ent to the cylindrical surface to be cut on said work piece and also having its cutting edge angularly related to a plane passing through the axis of rotation of said work piece in said work holder and normal to said tools mounted on said tool slidefor machining said radially extending surfaces, means for rotating said work holder, and means for feeding said tool slide whereby all of said tools simultaneously perform their machining operations.

3. In a'crankshaft lathe, means for supporting and rotating a crankshaft having a bearing comprising a cylindrical diameter and associated radially extending fillets, a "tool slide movable relative to said bearing, a shaving tool mounted on said tool slide for machining said cylindrical diameter portion, facing tools also mounted on said tool slide for machining said fillets, said tools being arranged to simultaneously perform their machining operations on the respective portions of said bearing, means for rotating said work holder, and means for feeding said tool slide.

4. In a crankshaft lathe, abase, a pair of tailstocks mounted on said base, axially movable centers in said tailstock adapted to engage the ends of a crankshaft, center drive chucking devices mounted on said base between said tailstocks, tool feeding devices mounted on said base between and each side of said center drive chucking devices, a tool bar mounted in each of-said tool feeding devices, cutting tools mounted on said tool bars for engaging bearing portions of 5 said crankshaft, a feed crankshaft moimtedonsaid center drive chucking devices and tool feeding devices, connecting means between said tool bars and said feed crankshaft, a single-hydraulic feed cylinder pivotally mounted on one of said tool 10 feeding devices and connected to said feed crankshaft for rocking same, fluid pressure means for actuating said hydraulic cylinder whereby all of said tool bars may be simultaneously fed relative to said crankshaft in said lathe, and means for 5 rotating said center drive chucking-devices.

5. In a crankshaft lathe, a base, tailstocks mounted on said base, axially movable centers insaid tailstocks adapted to engage the ends of a crankshaft in said lathe, center drive chucking 20 devices mounted on said base between said tailstocks, tool carrier units located between said center drive chucks and each side thereof and mounted on said base, a tool bar in each of said tool carrier units, cutting tools on said tool bars 25 adapted to engage bearing portions of said crankshaft, a feed crankshaft mounted on said tool carrier unit, connecting means between the throws of said crankshaft and each of said tool bars, a single hydraulic feed cylinder pivotally 3 mounted on a tool carrier unit between said center drive chucking devices, means for connecting said cylinder to said feed crankshaft, fluid pressure means for actuating said cylinder whereby said feed crankshaft may be rocked for simulss taneously feeding all of said tool bars, and means for rotating said center drive chucking devices.

6. In a crankshaft lathe, means for supporting androtatingacrankshaftsoasto'exposeall of its line bearings including its flange and stub 9 ends for machining operations, tool feeding devices movable relative to said crankshaft, shaving tools carried by said tool feeding devices for machining all of the cylindrical portions associated with said line bearings. flange, and stub 5 ends, facing tools carried by said tool feeding devices for machining all of the radially extending surfaces associated with said cylindrical portions, and means for actuating said tool feeding devices to cause all of said tools to simultaneously n perform their respective machining operations,

and means for rotating said supporting and rotating means. i

7. In a crankshaft lathe, means for supporting and rotating a crankshaft intermediate its ends. tool feeding devices adapted to be fed relative to all of the line bearings, flange, andstub ends of said crankshaft, shaving tools carried by said tool feeding devices for machining the diameters of the line bearings and also the diameters of n the stub end and flange end portions of said crankshaft, further tools also carried by said tool feeding devices adapted to face and neck the ill-- lets associated with said line bearing diameters and to neck and face the radially extending surgg faces associated with the stub, and flange end of the said crankshaft, means for rotating said supporting and rotating means, and means for simultaneously actuating all of. said tool feeding devices.

7o 8. In a lathe, a rotatable work holder adapted to engage a work piece having cylindrical and radially extending faces, a toolslidable to and from the axis of rotation of said work piece in the work holder, a cutting tool mountedon said 7 tool slide adapted to tangentially engage said cylindrical work surfaceto be machined, a'second cutting tool mounted on said tool slide adapted to engage said cylindrical surface perpendicular to a planetangent to the work surface at the point of engagement of said second mentioned I tool, means for rotating said work holder and means for feeding. said tool slide to cause said tools to simultaneously. act upon said work piece.

9. In a lathe, arotatable work holder adapted to engage a work piece having a cylindrical sur- 10 face and a radially extending surface associated theerwith, a tool slide associated with said work holder and adapted to feed perpendicular to the axis of rotation of saidwork piece in said work holder, a cutting'tool mounted on said tool slide adapted to engage said cylindrical surface tan-' gentially, a second cutting tool adapted to machine said radially extending surface and having a cutting edge adapted to engage said cylindrical surface from a direction perpendicular to a plane tangent to said cylindrical surface at the point of contact of said second mentioned tool,

means for rotating said work holder, and means 'workpiece in said work holder, a shaving tool 80 adapted to be fed tangentially past the cylindrical surface being machined, a facing tool mounted on said tool slide adapted to be fed D rn lldicular to said axis of rotation of said work piece for machining said radially extending surface of said work piece, means for rotating said work holder, and means for actuating said tool slide to cause said cutting tools to simultaneously operate upon said work piece.

, 11. In a lathe, a rotatable work holder adapted 40 to engage a work piece having cylindrical and radially extending surfaces, a shaving tool having its cutting edge lying in a plane which is parallel with the plane of relative feeding of the tool and work piece and having its cutting edge inclined at an angle to a plane passing through the axis of work rotation in the work holder and normal to said first mentioned plane, a facing tool associated with said shaving tool adapted to be fed simultaneously with said shaving tools to machine the radially extending surfaces of said work piece, means for rotating said work holder, and means for effecting feeding movements in said tool.

12. In a lathe, a tool holder adapted to be fed relative to the axis of rotation of a work piece in a work holder in said lathe, means on said tool holder for supporting a cutting tool with its cutting edge lying in a-plane whichisparallel with the plane of relative feeding of said tool holder and work piece and tangent to the surface of a diameter to be machined on said work piece and having its cutting edge inclined at an angle to a plane passing through the axis of work rotation and normal to said flrst mentioned plane, means on said tool holder for supporting a cutting tool having its cutting edge arranged to machine a radially extending surface on said work piece and having its cutting edge so arranged as to blend perfectly with the-surface machined by said flrst mentioned tool at the completion of the cutting cycle, means for rotating said work holder, and means for feeding said tool holder to effect simultaneous operation of said cutting tools on'sa'id tool holder.

13. In a crankshaft lathe, means for supporting and rotating 9. crankshaft, a tool bar movable to and from the axis of rotation of a work piece in said means, a. shaving tool fixed on said bar for machining a bearing diameter on said crankshaft, facing tools fixed on said bar for machining the fillets associated with said heating diameter, means for actuating said supporting and rotating means. and means for feeding said tool bar relative to said work piece in said work holder {or simultaneously accurately finishin the bearing diameter and associated fillets of said crankshaft.

Will-1AM F. IGROENE. HAROLD J. B.

4 CERTIFICATE OF CORRECTION. Patent No. 2,191, t7. rebmr zo, 19110.

WILLIAM F. GROENE, ET AL. It is hereby certified that error appears'in the printed specification of the above numbered patent requiring correction as follows: Pagei, first column, line 72, claim 8, for the words "tool slidable" read tool'elide movable; and second column, line 12, claim 9, for "theerwith" read there-' with; and that the said Letters Patent -sshouldbe readwith this correction therein that the same may conform to the record of the case in vthe Patent Office.

Signed and sealed this 16th day of April, A. D. 1910.

Leslie Frazer (Seal) Acting Commissioner of Patents 

